The Symposia, 1933 — 2003

1934: Aspects of Growth, Vol II

Organizer: Reginald Harris

The success of the 1933 Symposia emboldened Harris to undertake another in July of 1934. The biophysical approach to understanding biology remained the theme of the meeting, but now Harris chose topics relating to cell and organismal growth. "Growth", Harris wrote in the introduction to the Symposium volume, "is a very complex phenomenon...the more complex the problem, the more the biologist must use mathematics, physics and chemistry, and the more valuable cooperation with representatives of these several sciences becomes".

Topics covered ranged from what might be learned from the growth of crystals, through physical techniques that might be used to study molecular and cellular growth, to mathematical analysis of growth curves. Genetics made a small contribution to the meeting, with presentations that described mutations affecting growth. Milislav Demerec, for example, gave a rather theoretical discussion of the role of genes in development and, extrapolating data from radiation-induced mutations of genes on the X-chromosome, estimated the number of genes in Drosophila to be 2500. The current estimate based on the complete genome sequence of Drosophila is 14,000 genes and, remarkably, J. W. Gowen gave an estimate of 14,380 genes in his paper!

But the most interesting topic dealt with one of the footnotes of science, mitogenetic rays. Alexander Gurwitsch had described these rays, supposedly emitted by growing cells

and essential for cell division, and Otto Rahn gave a paper reviewing the evidence in support of mitogenetic rays. However, the eight pages of discussion show that his audience was far from convinced that such rays existed.

The number of participants had almost doubled to 58; perhaps more were encouraged to take part because the Symposium lasted only 12 days! Notable participants included Harold Urey who won the Nobel Prize for Chemistry later in the year; E. B. Wilson, one of the founders of the chromosomal foundation of genetics; and Ross G. Harrison, the great experimental embryologist; and Bill Astbury who, a few years later, took the first X-ray photographs of DNA.

In only their second year, the Symposia were already making a sufficient impact to attract a grant. The Rockefeller Foundation made a substantail contribution of $5000 towards the costs of the meeting.